SAN FRANCISCO (April 5, 2006) Exposure to nicotine the equivalent of smoking two packs of cigarets a day produced complicated, abnormal breathing development during the first 18 days of newborn rats, University of Arizona researchers report.
Ralph Fregosi, presenting the results at three American Physiological Society sessions at Experimental Biology, said his team "found that the required increase in breathing in response to reduced oxygen supply was lower in nicotine-exposed animals compared to the controls over their first nine days. This suggests that prenatal nicotine exposure reduces the ability of a neonatal animal to respond to low blood oxygen, which can lead to prolonged and possibly lethal apneas."
Between nine and 18 days, the situation reversed, and nicotine-exposed rats' response was actually higher than controls, showing an overall complicated, abnormal breathing development over the18 days. Fregosi is presenting at an APS "featured topic" as well as at two poster sessions:
1. Featured topic: Developmental changes in respiratory control in neonatal rodents, session 730, Plasticity track sponsored by the APS Respiration Section, Tuesday, April 4 10:30 a.m. Moscone Mezzanine West #270.
12:15 p.m.: Ralph Fregosi: "Influence of prenatal nicotine exposure on development of ventilatory responses to hypoxia and asphyxia." Funding: American Heart Association.
2. 12:45 p.m.- 3 p.m. Tuesday April 4, APS Physiology Developmental changes in respiratory control in neonatal rodents session 751.2/board #C479, "Influence of prenatal nicotine exposure on development of ventilatory responses to hypoxia and asphyxia." Research was by Ralph F. Fregosi, Amanda Rose Brown, Yu-Hsien Huang, and Seres Costy-Bennett , Department of Physiology, University of Arizona; Fregosi also is with the De